Arthur Q. Davis, the modernist architect who was instrumental in redefining New Orleans' skyline, died Wednesday at Ochsner Baptist Medical Center. He was 91. For 41 years, Mr. Davis and his partner, Nathaniel Curtis, formed the firm that designed such major buildings as the Superdome, the Rivergate Exhibition Center, the New Orleans Public Library's Main Branch, St. Frances Cabrini Catholic Church and the University of New Orleans Lakefront Arena.

In addition to projects in the United States, the firm designed buildings in Vietnam, Aruba, Scotland, Indonesia and Germany.

"It was the pivotal firm of the city from the 1950s on," said Tulane University Architecture Dean Kenneth Schwartz. "Their legacy is really extensive, not only in New Orleans but also across the world."

Mr. Davis was a lifelong New Orleanian who, according to a story on the Pirate's Alley Faulkner Society website, took an interest in architecture when he was a boy and happened on a mason laying bricks. The man patiently explained what he was doing, Mr. Davis said, and described how the blueprint, tacked to a piece of plywood, showed what he needed to do to build a chimney.

"I knew I wanted to become an architect from that moment," he said.

Mr. Davis graduated from Tulane University and went to work designing wooden structures that the Navy used to build flying boats.

During World War II, Mr. Davis served in the Navy, designing camouflage for the ships of the Pacific fleet, including the U.S.S. Missouri, the battleship aboard which Japan surrendered.

He studied at Harvard University, where he earned a master's degree after working under such modernist masters as Walter Gropius and Marcel Breuer.

He interned with Eero Saarinen before forming Curtis and Davis with his fellow Tulane alumnus. Curtis died in 1997.

In 1988, Mr. Davis established his own firm bearing his name. During that period, he designed the New Orleans Arena.

In 2009, he wrote a memoir, "It Happened by Design."

Throughout his career, "he always moved forward and never stepped back," said his son, Quint, producer and director of the New Orleans Jazz and Heritage Festival. "He was like some kind of nuclear reactor; he always had the energy to go forward."

Mr. Davis, a fellow of the American Institute of Architects, was the first chairman of the New Orleans Jazz and Heritage Foundation, a former president of the New Orleans Museum of Art's board of trustees and a former board member of the United Way, the Metropolitan Area Committee and the Preservation Resource Center Foundation.

In addition to his son, survivors include his wife, Mary Davis, whom he met while she was a Newcomb College student; a daughter, Pam Friedler; and three grandchildren.

A memorial service will be held Monday at 4 p.m. at the New Orleans Museum of Art.